Most watercrafts, including surfboards, use fins for stability when the craft is moving. A surfboard fin, or skeg, is a hydrofoil mounted at the tail of a surfboard or similar board to improve directional stability and control through foot-steering. Fins can provide lateral lift opposed to the water and stabilize the board's trajectory, allowing the surfer to control direction by varying their side-to-side weight distribution. The introduction of fins in the 1930s revolutionized surfing and board design. Surfboard fins may be arrayed in different numbers and configurations, while many different shapes, sizes, and materials have been made and used.
A “skeg” (an upright, streamlined, often raked keel) typically denotes one centrally-mounted stabilizer foil mounted perpendicularly to the riding surface, at the rear of the surfboard.
Smaller surfboard fins mounted near the edge (or “rail”) of the surfboard are known as “rail fins” and are seen in multi-fin arrangements (often in combination with a similarly-sized central fin further back on the board). Rail fins enable high-performance surfing, and are most often “single-foiled,” with one flat side and one “foiled” side, as seen on an airfoil, for greater lift.
Both a skeg and “rail fins” stabilize the motion of the surfboard. They also contribute to the desired effect of converting the (kinetic energy) push of the sloped wave face combined with the rider's mass on the sloped wave face (potential energy) into redirected energy—lift—the surfer deflects his surfboard and fins off the water of the wave face (and/or vice versa) to make forward progress across the wave face, or “down the line,” that is, parallel to the wave crest and beach—riding parallel to the crest (perpendicular to the pull of gravity down the wave's slope) in this way is known as “trimming” Lift (aka “drive”) from the board and its fin(s) is what enables all maneuvers in surfing.
A fin configuration with fins near the edge of the board stabilizes and contributes lift during turning maneuvers, which contributes to the board's ability to “hold” during turning maneuvers. Rail fins are often seen in addition to a central fin, but can be used without a central fin as well. Some of the most popular multi-fin configurations use two rail fins (a “twin-fin”), two rail fins plus a similar sized central fin mounted further back (e.g. a “Thruster”), or four fins (a “quad”). Rail fins are more or less engaged by the rider's heel and toes as they lean in the desired direction of their turn. As the rider does so, an “inside” rail fin sinks deeper and its angle of attack is increased, as is its lift-induced drag. Rail fins also add lift (known as “drive”) in trim and with greater holding ability, enable steeper wave faces to be ridden and higher speed “down the line.”
In Windsurfing and other watercraft based sports, a derivative of traditional surfing, skegs may also be used as a central stabilizing fin (hydrofoil) located at the rear of the board. A windsurfer's skeg also has the effect of producing lift, which allows the rider to direct the craft laterally against the lift the sail (itself an airfoil) produces. The skeg has undergone numerous phases of development and, as with other foils, its design is determined by the balance of the pressures it experiences in use, including lift, drag (physics), ventilation and stall (flight).
Many types of fins have been developed for use with surfboards and other watercraft. Materials used for producing fins are normally Plastic or Fiber. Fiber fins combine different materials to obtain better performance, and better weight and flotation ratios like honeycomb cores or bamboo cores, and are then glassed with fiber and sometimes reinforced with carbon fiber.
Older model surfboards and watercrafts mainly used glass-on fins that are permanently connected to the craft or surfboard through fiberglass. Glass-on fins, however, are broken easily and are hard to repair. These types of fins are rarely used nowadays as different types of fins have replaced them.
Removable Fin Systems, are one of the most common types of fins used today.
Removable fins can be unscrewed, or otherwise disconnected, from the surfboard/craft and be replaced by different fins, or be moved about the board/craft for a different setup in maneuverability and stability.
In the early 90's three Australian surfers invented the Fin Control System (FCS). Since its global release in 1994 FCS has become an industry standard; providing elite athletes and everyday surfers an abundance of fin designs and a platform to change the performance of their surfboard by changing fins. The system also streamlined the surfboard manufacturing process by making it easier to install fins into boards and repair damaged fins. One of the leading competitors to FCS fins is Futures fins. Using a single larger fin box, the manufacture claims the fins provide a stronger connection and more closely approximate the feeling of a glass-on fin.
However, severe problems often arise when extracting/removing or inserting fins from their fin boxes, for example when there is a need to replace them or take them off on the go. It is very hard, sometimes almost impossible, for an adult, let alone a child—as watercraft and water-board sports cater to all ages and genders—to extract and insert the fin by the hand. The problem is intensified by the fact that the fins are mostly used in water sports which involve salt water, sand and dust that tend to clog the fin in the fin box. In addition, the fin itself often gets scratched up and dented, which altogether makes removing and inserting a fin a very challenging task to achieve, without hurting yourself, or damaging: your watercraft, the fin and/or the fin box, during the process.
There remains a need, in the field of water-borne vehicles and watercrafts, for solutions, improved methodologies and tools, for inserting and removing fins—of various kinds of removable fin systems—from corresponding fin-box(es)/socket(s)/slot(s) of a watercraft, such as, but not limited to: surfboards, wakeboards, paddle boards and/or others.